Field of the Invention
The present invention relates to an aircraft having a structure for ensuring airtightness.
Description of the Related Art
A measuring device that measures a moisture content in the atmosphere is used for obtaining icing conditions on an airframe in a test flight of aircraft (JP2007-521463A).
The measuring device can be installed outside the airframe by fixing the measuring device to an arm that is provided on the airframe and extends out of the airframe.
In order to provide the arm to which the measuring device is fixed on the airframe, it is necessary for a member prepared in the airframe to receive an aerodynamic load applied to the measuring device and the arm during a flight. Since the aerodynamic load cannot be received only by a skin (an outer plate), it is difficult to achieve a configuration in which a proximal end of the arm is supported only on an outer surface side of the airframe without passing the arm through the airframe. Thus, the arm is required to penetrate the airframe to be coupled to a member that is prepared on an airframe inner side and can receive the aerodynamic load.
When the arm penetrates the airframe, it is necessary to ensure airtightness between the arm and the airframe in order to hold pressurization inside the airframe. Therefore, a gap between the arm and the airframe is sealed by a seal member, and the seal member is fixed to a receiving member.
When the aerodynamic load is applied to the arm during a flight, the arm is deformed. Since the arm penetrates the airframe, a load generated by the deformation of the arm is input to the airframe from the arm. It is necessary to prevent the airframe from being thereby damaged, or the seal member from being thereby displaced to impair the airtightness.
An object of the present invention is to provide an aircraft having an airtight structure capable of reliably holding airtightness inside an airframe even when a member penetrating the airframe between the inside and the outside is deformed by an aerodynamic load.